public class SubscriptExpression extends SingleItemFilter
operandEFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, INHERITED_CONTEXT, INSPECTION_CONTEXT, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, NAVIGATION_CONTEXT, NODE_VALUE_CONTEXT, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, W3C_CONSUMING, W3C_FREE_RANGING, W3C_GROUP_CONSUMING, W3C_MOTIONLESS, WATCH_METHOD| Constructor and Description |
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SubscriptExpression(Expression base,
Expression subscript)
Construct a SubscriptExpression
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| Modifier and Type | Method and Description |
|---|---|
int |
computeCardinality()
Get the static cardinality: this implementation is appropriate for [1] and [last()] which will always
return something if the input is non-empty
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Expression |
copy()
Copy an expression.
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boolean |
equals(Object other)
Compare two expressions to see if they are equal
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Item |
evaluateItem(XPathContext context)
Evaluate an expression as a single item.
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void |
explain(ExpressionPresenter destination)
Diagnostic print of expression structure.
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ExpressionCompiler |
getExpressionCompiler()
Return the compiler of the TailExpression expression
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Expression |
getSubscriptExpression()
Get the subscript expression
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int |
hashCode()
get HashCode for comparing two expressions.
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Iterator<Expression> |
iterateSubExpressions()
Get the immediate subexpressions of this expression
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Expression |
optimize(ExpressionVisitor visitor,
ExpressionVisitor.ContextItemType contextItemType)
Perform optimisation of an expression and its subexpressions.
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Expression |
promote(PromotionOffer offer,
Expression parent)
Promote this expression if possible
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boolean |
replaceSubExpression(Expression original,
Expression replacement)
Replace one subexpression by a replacement subexpression
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Pattern |
toStreamingPattern(Configuration config,
List<String> reasonForFailure)
Convert this expression to a streaming pattern (a pattern used internally to match nodes during
push processing of an event stream)
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String |
toString()
The toString() method for an expression attempts to give a representation of the expression
in an XPath-like form.
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Expression |
typeCheck(ExpressionVisitor visitor,
ExpressionVisitor.ContextItemType contextItemType)
Type-check the expression.
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computeSpecialProperties, displayOperator, getBaseExpression, getItemType, simplifyaddToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getExpressionName, getHostLanguage, getImplementationMethod, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getStreamability, getStreamingAdjunct, getSystemId, getSystemId, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterate, iterateEvents, iterateSubExpressionInfo, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toPattern, typeErrorpublic SubscriptExpression(Expression base, Expression subscript)
base - the expression to be filteredsubscript - the positional subscript filterpublic Expression typeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException
UnaryExpressiontypeCheck in class UnaryExpressionvisitor - an expression visitorcontextItemType - the static type of "." at the point where this expression is invoked.
The parameter is set to null if it is known statically that the context item will be undefined.
If the type of the context item is not known statically, the argument is set to
Type.ITEM_TYPEXPathException - if an error is discovered during this phase
(typically a type error)public Expression optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException
SingleItemFilterThis method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.
optimize in class SingleItemFiltervisitor - an expresion visitorcontextItemType - the static type of "." at the point where this expression is invoked.
The parameter is set to null if it is known statically that the context item will be undefined.
If the type of the context item is not known statically, the argument is set to
Type.ITEM_TYPEXPathException - if an error is discovered during this phase
(typically a type error)public Expression promote(PromotionOffer offer, Expression parent) throws XPathException
SingleItemFilterpromote in class SingleItemFilteroffer - details of the offer, for example the offer to move
expressions that don't depend on the context to an outer level in
the containing expressionparent - the containing expression in the expression treeXPathException - if any error is detectedpublic Expression copy()
copy in class Expressionpublic Iterator<Expression> iterateSubExpressions()
UnaryExpressioniterateSubExpressions in class UnaryExpressionpublic boolean replaceSubExpression(Expression original, Expression replacement)
replaceSubExpression in class UnaryExpressionoriginal - the original subexpressionreplacement - the replacement subexpressionpublic Expression getSubscriptExpression()
public boolean equals(Object other)
equals in class UnaryExpressionother - the other expressionpublic int hashCode()
UnaryExpressionhashCode in class UnaryExpressionpublic int computeCardinality()
computeCardinality in class SingleItemFilterStaticProperty.ALLOWS_ZERO_OR_ONE,
StaticProperty.EXACTLY_ONE, StaticProperty.ALLOWS_ONE_OR_MORE,
StaticProperty.ALLOWS_ZERO_OR_MOREpublic Pattern toStreamingPattern(Configuration config, List<String> reasonForFailure)
toStreamingPattern in class Expressionconfig - the Saxon configurationreasonForFailure - a list which will be populated with messages giving reasons why the
expression cannot be convertedpublic Item evaluateItem(XPathContext context) throws XPathException
ExpressionevaluateItem in class Expressioncontext - The context in which the expression is to be evaluatedXPathException - if any dynamic error occurs evaluating the
expressionpublic ExpressionCompiler getExpressionCompiler()
getExpressionCompiler in class Expressionpublic void explain(ExpressionPresenter destination)
explain in class UnaryExpressiondestination - the expression presenter used to display the structurepublic String toString()
The toString() method for an expression attempts to give a representation of the expression in an XPath-like form.
For subclasses of Expression that represent XPath expressions, the result should always be a string that parses as an XPath 3.0 expression.
toString in class UnaryExpressionCopyright (c) 2004-2013 Saxonica Limited. All rights reserved.